You have a mountain of books so what do you do with them? There are many options and these are a few.
Discard: Any books that have mold or mildew should be discarded. Old textbooks, old dictionaries, encyclopedias and most magazines should be recycled if possible. It is o.k. to discard them if the recycler will not accept them. Any books with missing pages should also be discarded.
Donate or Giveaway: Many charities and thrift stores accept book donations. This includes Goodwill, Volunteers of America, The Salvation Army, Library Thrift Stores (also known as Friends of the Library), and churches. These organizations will sell the books, usually for 25-cents to $2 each to raise money for their organization. If you want to receive a tax deduction for your donation, be sure you comply with the IRS rules for documenting charitable contributions. You may not deduct more than the Fair Market Value (FMV) of the books. Determining this value can be confusing and it is difficult to provide rock-solid evidence of their value.
To avoid falling afoul of IRS regulations, I suggest a more creative approach. Sell as many of your books as you can to a book dealer and give the money you receive to the charity of your choice. This will allow you to raise money for ANY qualified charity, not just those that resell books. Furthermore, by giving a cash donation, you have a non-disputable record of your donation and you can fill out your tax forms with peace of mind.
Most brick-and-mortar bookstores will require you to bring your books to their store in order for them to evaluate and purchase your collection. Most online booksellers such as Crestview Books (www.CrestviewBooks.com) will come to your home so that you don't have to load and tote heavy boxes of books. The offer from a reputable online dealer should be at least as much as that offered by a brick-and-mortar store. If you do not know the dealer, or if they are not recommended by a trusted friend or professional organizer, do not let them into your home unless you have someone with you.
Using this sell-and-donate strategy is a win-win-win! You win because you have evidence of your donation. Your charity wins because they get money they can use right away without having to use valuable time cleaning, storing and sorting them for sale. The small business book dealer wins by obtaining needed inventory to keep the business running.
Sell: Sell them yourself at a garage sale or online at a website such as eBay. For your garage sale you should price your books at or below what they would bring at a thrift store. Selling your books online will probably give you the largest amount of money but it is not quick and easy.
If you have a book that you believe may be of significant value, contact an established dealer or auction house for an opinion before you let go of a real treasure!